Re: KASAN: use-after-free Read in alloc_pid

From: Eric W. Biederman
Date: Tue Apr 24 2018 - 12:34:58 EST


Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> writes:

> On 2018/04/10 23:33, Tetsuo Handa wrote:
>> syzbot wrote:
>>> syzbot has found reproducer for the following crash on upstream commit
>>> c18bb396d3d261ebbb4efbc05129c5d354c541e4 (Tue Apr 10 00:04:10 2018 +0000)
>>> Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
>>> syzbot dashboard link:
>>> https://syzkaller.appspot.com/bug?extid=7a1cff37dbbef9e7ba4c
>>>
>> While we are waiting for
>>
>> rpc_pipefs: fix double-dput()
>> rpc_pipefs: deal with early sget() failures
>> kernfs: deal with early sget() failures
>> procfs: deal with early sget() failures
>> orangefs_kill_sb(): deal with allocation failures
>> nfsd_umount(): deal with early sget() failures
>> nfs: avoid double-free on early sget() failures
>> jffs2_kill_sb(): deal with failed allocations
>> hypfs_kill_super(): deal with failed allocations
>>
>> in https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git/log/?h=for-linus ,
>> I think the patch at
>>
>> WARNING in kill_block_super
>> https://syzkaller.appspot.com/bug?id=588996a25a2587be2e3a54e8646728fb9cae44e7
>>
>> is better.
>>
>
> OK. The patch was sent to linux.git as commit 8e04944f0ea8b838.
>
> #syz fix: mm,vmscan: Allow preallocating memory for
> register_shrinker().

Sigh no fixes tag on the commit you sent to Linus, and no
cc'ing of stable.

Can you please update the stable folks that 9ee332d99e4d ("sget():
handle failures of register_shrinker()") is fixed with the commit you
just sent to Linus?

Thank you,
Eric